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Fair Value Measurements (Change in Fair Value of Securities Using Level 3 Inputs) (Details) - Available-for-sale Securities [Member] - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Obligations of States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	$ 2,894	$ 0
Total net (losses) gains for the period included in OCI	9	(36)
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	5,101	2,890
Transfers out of Level 3	0	0
Fair value, September 30	8,004	2,854
Period change unrealized losses in earnings for assets held at period end	0	0
Period change unrealized gains in OCI for assets held at period end	9	(36)
Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	70,700	17,051
Total net (losses) gains for the period included in OCI	2,607	(2,415)
Purchases	43,833	19,002
Sales	0	0
Issuances	0	0
Settlements	(210)	(138)
Transfers into Level 3	981	4,592
Transfers out of Level 3	(7,454)	0
Fair value, September 30	110,286	37,636
Period change unrealized losses in earnings for assets held at period end	(185)	(456)
Period change unrealized gains in OCI for assets held at period end	2,607	(2,415)
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	56,375	17,034
Total net (losses) gains for the period included in OCI	206	732
Purchases	19,041	11,751
Sales	0	0
Issuances	0	0
Settlements	(1,750)	(1,030)
Transfers into Level 3	3,226	26,401
Transfers out of Level 3	(14,643)	(9,924)
Fair value, September 30	62,429	44,720
Period change unrealized losses in earnings for assets held at period end	(35)	(247)
Period change unrealized gains in OCI for assets held at period end	206	732
Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	129,969	34,085
Total net (losses) gains for the period included in OCI	2,822	(1,719)
Purchases	62,874	30,753
Sales	0	0
Issuances	0	0
Settlements	(1,960)	(1,168)
Transfers into Level 3	9,308	33,883
Transfers out of Level 3	(22,097)	(9,924)
Fair value, September 30	180,719	85,210
Period change unrealized losses in earnings for assets held at period end	(220)	(703)
Period change unrealized gains in OCI for assets held at period end	2,822	(1,719)
Gain (Loss) on Investments [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	0	0
Gain (Loss) on Investments [Member] | Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	(185)	(456)
Gain (Loss) on Investments [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	(35)	(247)
Gain (Loss) on Investments [Member] | Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	(220)	(703)
Net Investment Income Earned [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	0	0
Net Investment Income Earned [Member] | Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	14	0
Net Investment Income Earned [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	9	3
Net Investment Income Earned [Member] | Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net (losses) gains for the period included in net income	$ 23	$ 3

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Change in unrealized gains (losses) for the period included in comprehensive income for assets held at the end of the period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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